Exhibit
10.4


 


SECOND
AMENDED AND RESTATED GUARANTY


 


This
SECOND AMENDED AND RESTATED GUARANTY, dated as of August 5, 2020 (this “Guaranty”), is made by each
of the undersigned (each a “Guarantor”, and collectively, the “Guarantors”), in favor of
Alto Opportunity Master Fund, SPC - Segregated Master Portfolio B, in its capacity as collateral agent (in such capacity, the
“Collateral Agent” as hereinafter further defined) for the “Buyers” party to the Securities Purchase
Agreements (each as defined below).


 


W
I T N E S S E T H :


 


WHEREAS,
PAVmed Inc., a Delaware corporation with offices located at One Grand Central Place, Suite 4600, New York, NY 10165 (the “Company”),
and each other party thereto are parties to (i) the Securities Purchase Agreement, dated as of November 3, 2019 (as amended, modified,
supplemented, extended, renewed, restated or replaced from time to time, the “2019 Securities Purchase Agreement”)
pursuant which the Company sold senior secured convertible notes (the “2019 Notes”) to the party listed as
a “Buyer” on the Schedule of Buyers attached to the 2019 Securities Purchase Agreement (the “2019 Buyers”),
and (ii) the Securities Purchase Agreement, dated as of August 5, 2020 (as amended, restated, extended, replaced or otherwise
modified from time to time, the “2020 Securities Purchase Agreement” and together with the 2019 Securities
Purchase Agreement, the “Securities Purchase Agreements”), pursuant to which the Company shall be required
to sell to the parties listed as “Buyer” on the Schedule of Buyers attached to the 2020 Securities Purchase Agreement
(the “2020 Buyer”), and the 2020 Buyer shall purchase or have the right to purchase, a senior secured convertible
note of the Company (the “2020 Note”) issued pursuant thereto (as such 2019 Notes or 2020 Note may be amended,
restated, extended, replaced or otherwise modified from time to time in accordance with the terms thereof, collectively, the “Notes”);


 


WHEREAS,
the Securities Purchase Agreements require that the Guarantors execute and deliver to the Collateral Agent, (i) a guaranty guaranteeing
all of the obligations of the Company under the Securities Purchase Agreements, the Notes issued thereunder and the other Transaction
Documents (as defined below); and (ii) a Security and Pledge Agreement granting the Collateral Agent a lien on and security interest
in all of their assets and properties;


 


WHEREAS,
in connection with the execution of the 2019 Securities Purchase Agreement, Lucid Diagnostics, Inc. executed and delivered an
Amended and Restated Guaranty dated as of November 4, 2019, in favor of Alto Opportunity Master Fund, SPC - Segregated Master
Portfolio B, in its capacity as collateral agent (the “Existing Guaranty”);


 


WHEREAS,
the parties hereto wish to amend and restate the Existing Guaranty in its entirety as provided for herein; and


 


WHEREAS,
each Guarantor has determined that the execution, delivery and performance of this Guaranty directly benefits, and is in the best
interest of, such Guarantor.


 


NOW,
THEREFORE, in consideration of the premises and the agreements herein and in order to induce the Buyers to perform under each
of the Securities Purchase Agreements, each Guarantor hereby agrees with each Buyer as follows:


 




    	 



     


    

 


Section
1. Definitions. Reference is hereby
made to the Securities Purchase Agreements and the Notes for a statement of the terms thereof. All terms used in this
Guaranty and the recitals hereto which are defined in the Securities Purchase Agreements or the Notes, and which are not
otherwise defined herein shall have the same meanings herein as set forth therein. In addition, the following terms when used
in the Guaranty shall have the meanings set forth below:


 


“Bankruptcy
Code” means Chapter 11 of Title 11 of the United States Code, 11 U.S.C §§ 101 et seq. (or other applicable
bankruptcy, insolvency or similar laws).


 


“Business
Day” means any day other than Saturday, Sunday or other day on which commercial banks in New York City are authorized
or required by law to remain closed.


 


“Buyers”
means the 2019 Buyers and the 2020 Buyer; and each, individually, a “Buyer”.


 


“Capital
Stock” means (i) with respect to any Person that is a corporation, any and all shares, interests, participations or
other equivalents (however designated and whether or not voting) of corporate stock (including, without limitation, any warrants,
options, rights or other securities exercisable or convertible into equity interests or securities of such Person), and (ii) with
respect to any Person that is not a corporation, any and all partnership, membership or other equity interests of such Person.


 


“Collateral”
means all assets and properties of the Company and each Guarantor, wherever located and whether now or hereafter existing
and whether now owned or hereafter acquired, of every kind and description, tangible or intangible, including, without limitation,
the collateral described in Section 2 of the Security Agreement.


 


“Collateral
Agent” shall have the meaning set forth in the recitals hereto.


 


“Company”
shall have the meaning set forth in the recitals hereto.


 


“Governmental
Authority” means any nation or government, any Federal, state, city, town, municipality, county, local, foreign or other
political subdivision thereof or thereto and any department, commission, board, bureau, instrumentality, agency or other entity
exercising executive, legislative, judicial, taxing, regulatory or administrative powers or functions of or pertaining to government.


 


“Guaranteed
Obligations” shall have the meaning set forth in Section 2 of this Guaranty.


 


“Guarantor”
or “Guarantors” shall have the meaning set forth in the recitals hereto.


 


“Indemnified
Party” shall have the meaning set forth in Section 13(a) of this Guaranty


 


“Insolvency
Proceeding” means any proceeding commenced by or against any Person under any provision of the Bankruptcy Code or under
any other bankruptcy or insolvency law, assignments for the benefit of creditors, formal or informal moratoria, compositions,
or extensions generally with creditors, or proceedings seeking reorganization, arrangement, or other similar relief.


 




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“Notes”
shall have the meaning set forth in the recitals hereto.


 


“Obligations”
shall have the meaning set forth in Section 3 of the Security Agreement.


 


“Other
Taxes” shall have the meaning set forth in Section 12(a)(iv) of this Guaranty.


 


“Paid
in Full” or “Payment in Full” means the indefeasible payment in full in cash of all of the Guaranteed Obligations.


 


“Person”
means an individual, corporation, limited liability company, partnership, association, joint-stock company, trust, unincorporated
organization, joint venture or other enterprise or entity or Governmental Authority.


 


“Securities
Purchase Agreements” shall have the meaning set forth in the recitals hereto.


 


“Security
Agreement” means the Second Amended and Restated Security Agreement, dated as of August 5, 2020, by and among
the Company, the grantors party thereto, and Collateral Agent.


 


“Subsidiary”
means any Person in which a Guarantor directly or indirectly, (i) owns any of the outstanding Capital Stock or holds any equity
or similar interest of such Person or (ii) controls or operates all or any part of the business, operations or administration
of such Person, and all of the foregoing, collectively, “Subsidiaries”.


 


“Taxes”
shall have the meaning set forth in Section 12(a) of this Guaranty.


 


“Transaction
Party” means the Company and each Guarantor, collectively, “Transaction Parties”.


 


“Transaction
Documents”  shall have the meaning set forth in the Security Agreement.


 


Section
2. Guaranty.


 


(a)
The Guarantors, jointly and severally, hereby unconditionally and irrevocably, guaranty to the Collateral Agent, for the benefit
of the Collateral Agent and the Buyers, the punctual payment, as and when due and payable, by stated maturity or otherwise, of
all Obligations, including, without limitation, all interest, make-whole and other amounts that accrue after the commencement
of any Insolvency Proceeding of the Company or any Guarantor, whether or not the payment of such interest, make-whole and/or other
amounts are enforceable or are allowable in such Insolvency Proceeding, and all fees, interest, premiums, penalties, causes of
actions, costs, commissions, expense reimbursements, indemnifications and all other amounts due or to become due under any of
the Transaction Documents (all of the foregoing collectively being the “Guaranteed Obligations”), and agrees
to pay any and all reasonable costs and expenses (including counsel fees and expenses) incurred by the Collateral Agent in enforcing
any rights under this Guaranty or any other Transaction Document. Without limiting the generality of the foregoing, each Guarantor’s
liability hereunder shall extend to all amounts that constitute part of the Guaranteed Obligations and would be owed by the Company
to the Collateral Agent or any Buyer under any of the Securities Purchase Agreements and the Notes but for the fact that they
are unenforceable or not allowable due to the existence of an Insolvency Proceeding involving any Transaction Party.


 




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(b)
Each Guarantor, and by its acceptance of this Guaranty, the Collateral Agent and each Buyer, hereby confirms that it is the intention
of all such Persons that this Guaranty and the Guaranteed Obligations of each Guarantor hereunder not constitute a fraudulent
transfer or conveyance for purposes of the Bankruptcy Code, the Uniform Fraudulent Conveyance Act, the Uniform Fraudulent Transfer
Act or any similar foreign, federal, provincial, state, or other applicable law to the extent applicable to this Guaranty and
the Guaranteed Obligations of each Guarantor hereunder. To effectuate the foregoing intention, the Collateral Agent, the Buyers
and the Guarantors hereby irrevocably agree that the Guaranteed Obligations of each Guarantor under this Guaranty at any time
shall be limited to the maximum amount as will result in the Guaranteed Obligations of such Guarantor under this Guaranty not
constituting a fraudulent transfer or conveyance.


 


Section
3. Guaranty Absolute; Continuing Guaranty;
Assignments.


 


(a)
The Guarantors, jointly and severally, guaranty that the Guaranteed Obligations will be paid strictly in accordance with the terms
of the Transaction Documents, regardless of any law, regulation or order now or hereafter in effect in any jurisdiction affecting
any of such terms or the rights of the Collateral Agent or any Buyer with respect thereto. The obligations of each Guarantor under
this Guaranty are independent of the Guaranteed Obligations, and a separate action or actions may be brought and prosecuted against
any Guarantor to enforce such obligations, irrespective of whether any action is brought against any Transaction Party or whether
any Transaction Party is joined in any such action or actions. The liability of any Guarantor under this Guaranty shall be as
a primary obligor (and not merely as a surety) and shall be irrevocable, absolute and unconditional irrespective of, and each
Guarantor hereby irrevocably waives, to the extent permitted by law, any defenses it may now or hereafter have in any way relating
to, any or all of the following:


 


(i)
any lack of validity or enforceability of any Transaction Document;


 


(ii)
any change in the time, manner or place of payment of, or in any other term of, all or any of the Guaranteed Obligations, or any
other amendment or waiver of or any consent to departure from any Transaction Document, including, without limitation, any increase
in the Guaranteed Obligations resulting from the extension of additional credit to any Transaction Party or extension of the maturity
of any Guaranteed Obligations or otherwise;


 


(iii)
any taking, exchange, release or non-perfection of any Collateral;


 




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(iv)
any taking, release or amendment or waiver of or consent to departure from any other guaranty, for all or any of the Guaranteed
Obligations;


 


(v)
any change, restructuring or termination of the corporate, limited liability company or partnership structure or existence of
any Transaction Party;


 


(vi)
any manner of application of Collateral or any other collateral, or proceeds thereof, to all or any of the Guaranteed Obligations,
or any manner of sale or other disposition of any Collateral or any other collateral for all or any of the Guaranteed Obligations
or any other Obligations of any Transaction Party under the Transaction Documents or any other assets of any Transaction Party
or any of its Subsidiaries;


 


(vii)
any failure of the Collateral Agent or any Buyer to disclose to any Transaction Party any information relating to the business,
condition (financial or otherwise), operations, performance, properties or prospects of any other Transaction Party now or hereafter
known to the Collateral Agent or any Buyer (each Guarantor waiving any duty on the part of the Collateral Agent or any Buyer to
disclose such information);


 


(viii)
taking any action in furtherance of the release of any Guarantor or any other Person that is liable for the Obligations from all
or any part of any liability arising under or in connection with any Transaction Document without the prior written consent of
the Collateral Agent; or


 


(ix)
any other circumstance (including, without limitation, any statute of limitations) or any existence of or reliance on any representation
by the Collateral Agent or any Buyer that might otherwise constitute a defense available to, or a discharge of, any Transaction
Party or any other guarantor or surety.


 


(b)
This Guaranty shall continue to be effective or be reinstated, as the case may be, if at any time any payment of any of the Guaranteed
Obligations is rescinded or must otherwise be returned by the Collateral Agent, any Buyer, or any other Person upon the insolvency,
bankruptcy or reorganization of any Transaction Party or otherwise, all as though such payment had not been made.


 


(c)
This Guaranty is a continuing guaranty and shall (i) remain in full force and effect until Payment in Full of the Guaranteed Obligations
(other than inchoate indemnity obligations) and shall not terminate for any reason prior to the respective Maturity Date of each
Note (other than Payment in Full of the Guaranteed Obligations) and (ii) be binding upon each Guarantor and its respective successors
and assigns. This Guaranty shall inure to the benefit of and be enforceable by the Collateral Agent, the Buyers, and their respective
successors, and permitted pledgees, transferees and assigns. Without limiting the generality of the foregoing sentence, the Collateral
Agent or any Buyer may pledge, assign or otherwise transfer all or any portion of its rights and obligations under and subject
to the terms of any Transaction Document to any other Person, and such other Person shall thereupon become vested with all the
benefits in respect thereof granted to the Collateral Agent or such Buyer (as applicable) herein or otherwise, in each case as
provided in the Securities Purchase Agreements or such Transaction Document.


 




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Section
4. Waivers. To the extent permitted by
applicable law, each Guarantor hereby waives promptness, diligence, protest, notice of acceptance and any other notice or formality
of any kind with respect to any of the Guaranteed Obligations and this Guaranty and any requirement that the Collateral Agent
exhaust any right or take any action against any Transaction Party or any other Person or any Collateral. Each Guarantor acknowledges
that it will receive direct and indirect benefits from the financing arrangements contemplated herein and that the waiver set
forth in this Section 4 is knowingly made in contemplation of such benefits. The Guarantors hereby waive any right to revoke this
Guaranty, and acknowledge that this Guaranty is continuing in nature and applies to all Guaranteed Obligations, whether existing
now or in the future. Without limiting the foregoing, to the extent permitted by applicable law, each Guarantor hereby unconditionally
and irrevocably waives (a) any defense arising by reason of any claim or defense based upon an election of remedies by the Collateral
Agent or any Buyer that in any manner impairs, reduces, releases or otherwise adversely affects the subrogation, reimbursement,
exoneration, contribution or indemnification rights of such Guarantor or other rights of such Guarantor to proceed against any
of the other Transaction Parties, any other guarantor or any other Person or any Collateral, and (b) any defense based on any
right of set-off or counterclaim against or in respect of the Guaranteed Obligations of such Guarantor hereunder. Each Guarantor
hereby unconditionally and irrevocably waives any duty on the part of the Collateral Agent or any Buyer to disclose to such Guarantor
any matter, fact or thing relating to the business, condition (financial or otherwise), operations, performance, properties or
prospects of any other Transaction Party or any of its Subsidiaries now or hereafter known by the Collateral Agent or a Buyer.


 


Section
5. Subrogation. No Guarantor may exercise
any rights that it may now or hereafter acquire against any Transaction Party or any other guarantor that arise from the existence,
payment, performance or enforcement of any Guarantor’s obligations under this Guaranty, including, without limitation, any
right of subrogation, reimbursement, exoneration, contribution or indemnification and any right to participate in any claim or
remedy of the Collateral Agent or any Buyer against any Transaction Party or any other guarantor or any Collateral, whether or
not such claim, remedy or right arises in equity or under contract, statute or common law, including, without limitation, the
right to take or receive from any Transaction Party or any other guarantor, directly or indirectly, in cash or other property
or by set-off or in any other manner, payment or security solely on account of such claim, remedy or right, unless and until there
has been Payment in Full of the Guaranteed Obligations. If any amount shall be paid to a Guarantor in violation of the immediately
preceding sentence at any time prior to Payment in Full of the Guaranteed Obligations and all other amounts payable under this
Guaranty, such amount shall be held in trust for the benefit of the Collateral Agent and shall forthwith be paid to the Collateral
Agent to be credited and applied to the Guaranteed Obligations and all other amounts payable under this Guaranty, whether matured
or unmatured, in accordance with the terms of the Transaction Document, or to be held as Collateral for any Guaranteed Obligations
or other amounts payable under this Guaranty thereafter arising. If (a) any Guarantor shall make payment to the Collateral Agent
of all or any part of the Guaranteed Obligations, and (b) there has been Payment in Full of the Guaranteed Obligations, the Collateral
Agent will, at such Guarantor’s request and expense, execute and deliver to such Guarantor appropriate documents, without
recourse and without representation or warranty, necessary to evidence the transfer by subrogation to such Guarantor of an interest
in the Guaranteed Obligations resulting from such payment by such Guarantor.


 




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Section
6. Representations, Warranties and Covenants.


 


(a)
Each Guarantor hereby represents and warrants as of the date first written above as follows:


 


(i)
such Guarantor (A) is a corporation, limited liability company or limited partnership duly organized, validly existing and in
good standing under the laws of the jurisdiction of its organization as set forth on the signature pages hereto, (B) has all requisite
corporate, limited liability company or limited partnership power and authority to conduct its business as now conducted and as
presently contemplated and to execute, deliver and perform its obligations under this Guaranty and each other Transaction Document
to which such Guarantor is a party, and to consummate the transactions contemplated hereby and thereby and (C) is duly qualified
to do business and is in good standing in each jurisdiction in which the character of the properties owned or leased by it or
in which the transaction of its business makes such qualification necessary except where the failure to be so qualified (individually
or in the aggregate) would not result in a Material Adverse Effect.


 


(ii)
The execution, delivery and performance by such Guarantor of this Guaranty and each other Transaction Document to which such Guarantor
is a party (A) have been duly authorized by all necessary corporate, limited liability company or limited partnership action,
(B) do not and will not contravene its charter, articles, certificate of formation or by-laws, its limited liability company or
operating agreement or its certificate of partnership or partnership agreement, as applicable, or any applicable law or any contractual
restriction binding on such Guarantor or its properties do not and will not result in or require the creation of any lien, security
interest or encumbrance (other than pursuant to any Transaction Document) upon or with respect to any of its properties, and (C)
do not and will not result in any default, noncompliance, suspension, revocation, impairment, forfeiture or nonrenewal of any
material permit, license, authorization or approval applicable to it or its operations or any of its properties.


 


(iii)
No authorization or approval or other action by, and no notice to or filing with, any Governmental Authority or other Person is
required in connection with the due execution, delivery and performance by such Guarantor of this Guaranty or any of the other
Transaction Documents to which such Guarantor is a party (other than expressly provided for in any of the Transaction Documents).


 


(iv)
This Guaranty has been duly executed and delivered by each Guarantor and is, and each of the other Transaction Documents to which
such Guarantor is or will be a party, when executed and delivered, will be, a legal, valid and binding obligation of such Guarantor,
enforceable against such Guarantor in accordance with its terms, except as may be limited by the Bankruptcy Code or other applicable
bankruptcy, insolvency, reorganization, moratorium, fraudulent conveyance, suretyship or similar laws and equitable principles
(regardless of whether enforcement is sought in equity or at law).


 


(v)
There is no pending or, to the best knowledge of such Guarantor, threatened action, suit or proceeding against such Guarantor
or to which any of the properties of such Guarantor is subject, before any court or other Governmental Authority or any arbitrator
that (A) if adversely determined, could reasonably be expected to have a Material Adverse Effect or (B) relates to this Guaranty
or any of the other Transaction Documents to which such Guarantor is a party or any transaction contemplated hereby or thereby.


 




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(vi)
Such Guarantor (A) has read and understands the terms and conditions of the Securities Purchase Agreements and the other Transaction
Documents, and (B) now has and will continue to have independent means of obtaining information concerning the affairs, financial
condition and business of the Company and the other Transaction Parties, and has no need of, or right to obtain from the Collateral
Agent or any Buyer, any credit or other information concerning the affairs, financial condition or business of the Company or
the other Transaction Parties.


 


(vii)
There are no conditions precedent to the effectiveness of this Guaranty that have not been satisfied or waived.


 


(b)
Each Guarantor (so long as it is a Guarantor) covenants and agrees that until Payment in Full of the Guaranteed Obligations, it
will comply with each of the covenants (except to the extent applicable only to a public company) which are set forth in Section
4 of each of the Securities Purchase Agreements as if such Guarantor were a party thereto.


 


Section
7. Right of Set-off. Upon the occurrence
and during the continuance of any Event of Default, the Collateral Agent and any Buyer may, and is hereby authorized to, at any
time and from time to time, without notice to the Guarantors (any such notice being expressly waived by each Guarantor) and to
the fullest extent permitted by law, set-off and apply any and all deposits (general or special, time or demand, provisional or
final) at any time held and other indebtedness at any time owing by the Collateral Agent or any Buyer to or for the credit or
the account of any Guarantor against any and all obligations of the Guarantors now or hereafter existing under this Guaranty or
any other Transaction Document, irrespective of whether or not the Collateral Agent or any Buyer shall have made any demand under
this Guaranty or any other Transaction Document and although such obligations may be contingent or unmatured. The Collateral Agent
and each Buyer agrees to notify the relevant Guarantor promptly after any such set-off and application made by the Collateral
Agent or such Buyer, provided that the failure to give such notice shall not affect the validity of such set-off and application.
The rights of the Collateral Agent or any Buyer under this Section 7 are in addition to other rights and remedies (including,
without limitation, other rights of set-off) which the Collateral Agent or such Buyer may have under this Guaranty or any other
Transaction Document in law or otherwise.


 


Section
8. Limitation on Guaranteed Obligations.


 


(a)
Notwithstanding any provision herein contained to the contrary, each Guarantor’s liability hereunder shall be limited to
an amount not to exceed as of any date of determination the greater of:


 


(i)
the amount of all Guaranteed Obligations, plus interest thereon at the applicable Interest Rates as specified in the Notes; and


 




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(ii)
the amount which could be claimed by the Collateral Agent from any Guarantor under this Guaranty without rendering such claim
voidable or avoidable under the Bankruptcy Code or under any applicable state Uniform Fraudulent Transfer Act, Uniform Fraudulent
Conveyance Act or similar statute or common law after taking into account, among other things, Guarantor’s right of contribution
and indemnification.


 


(b)
Each Guarantor agrees that the Guaranteed Obligations may at any time and from time to time exceed the amount of the liability
of such Guarantor hereunder without impairing the guaranty hereunder or affecting the rights and remedies of the Collateral Agent
or any Buyer hereunder or under applicable law.


 


(c)
No payment made by the Company, any Guarantor, any other guarantor or any other Person or received or collected by the Collateral
Agent or any other Buyer from the Company, any of the Guarantors, any other guarantor or any other Person by virtue of any action
or proceeding or any set-off or appropriation or application at any time or from time to time in reduction of or in payment of
the Guaranteed Obligations shall be deemed to modify, reduce, release or otherwise affect the liability of any Guarantor hereunder
which shall, notwithstanding any such payment (other than any payment made by such Guarantor in respect of the Guaranteed Obligations
or any payment received or collected from such Guarantor in respect of the Guaranteed Obligations), remain liable for the Guaranteed
Obligations up to the maximum liability of such Guarantor hereunder until after all of the Guaranteed Obligations and all other
amounts payable under this Guaranty shall have been Paid in Full.


 


(d)
Upon any Guarantor ceasing to be a Significant Subsidiary (to the extent the circumstances as a result of which it ceases to
be a Significant Subsidiary are not prohibited by the terms of the Transaction Documents), such Guarantor shall be
automatically released from its obligations under this Guaranty. The Collateral Agent shall execute any documents reasonably
requested by the Company or any Guarantor to evidence the release of such Guarantor from its obligations hereunder, provided
that Company or Guarantor, as applicable, agrees to pay all reasonable costs and expenses of the Collateral Agent (including
the reasonable and documented fees and expenses of counsel for the Collateral Agent) in connection with such release and
execution of such documents.


 


Section
9. Notices, Etc. Any notices, consents,
waivers or other communications required or permitted to be given under the terms of this Guaranty must be in writing and will
be deemed to have been delivered: (i) upon receipt, when delivered personally; (ii) upon receipt, when sent by facsimile (provided
confirmation of transmission is mechanically or electronically generated and kept on file by the sending party); or (iii) one
(1) Business Day after deposit with an nationally recognized overnight courier service with next day delivery specified, in each
case, properly addressed to the party to receive the same. All notices and other communications provided for hereunder shall be
sent, if to any Guarantor, to the Company’s address and/or facsimile number, or if to the Collateral Agent or any Buyer,
to it at its respective address and/or facsimile number, each as set forth in Section 9(f) of each of the Securities Purchase
Agreements.


 




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Section
10. Governing Law; Jurisdiction. All questions
concerning the construction, validity, enforcement and interpretation of this Guaranty shall be governed by the internal laws
of the State of New York, without giving effect to any choice of law or conflict of law provision or rule (whether of the State
of New York or any other jurisdictions) that would cause the application of the laws of any jurisdiction other than the State
of New York. Each Guarantor hereby irrevocably submits to the exclusive jurisdiction of the state and federal courts sitting in
The City of New York, Borough of Manhattan, for the adjudication of any dispute hereunder or in connection herewith or under any
of the other Transaction Documents or with any transaction contemplated hereby or thereby, and hereby irrevocably waives, and
agrees not to assert in any suit, action or proceeding, any claim, obligation or defense that it is not personally subject to
the jurisdiction of any such court, that such suit, action or proceeding is brought in an inconvenient forum or that the venue
of such suit, action or proceeding is improper. Each party hereby irrevocably waives personal service of process and consents
to process being served in any such suit, action or proceeding by mailing a copy thereof to such party at the address for such
notices to it under Section 9(f) of each of the Securities Purchase Agreements and agrees that such service shall constitute good
and sufficient service of process and notice thereof. Nothing contained herein shall be deemed to limit in any way any right to
serve process in any manner permitted by law. Nothing contained herein shall be deemed or operate to preclude the Collateral Agent
or the Buyers from bringing suit or taking other legal action against any Guarantor in any other jurisdiction to collect on a
Guarantor’s obligations or to enforce a judgment or other court ruling in favor of the Collateral Agent or a Buyer.


 


Section
11. WAIVER OF JURY TRIAL, ETC. EACH GUARANTOR
HEREBY IRREVOCABLY WAIVES ANY RIGHT IT MAY HAVE TO, AND AGREES NOT TO REQUEST, A JURY TRIAL FOR THE ADJUDICATION OF ANY DISPUTE
HEREUNDER OR UNDER ANY OTHER TRANSACTION DOCUMENT OR IN CONNECTION WITH OR ARISING OUT OF THIS GUARANTY, ANY OTHER TRANSACTION
DOCUMENT OR ANY TRANSACTION CONTEMPLATED HEREBY OR THEREBY.


 


Section
12. Taxes.


 


(a)
All payments made by any Guarantor hereunder or under any other Transaction Document shall be made in accordance with the terms
of the respective Transaction Document and shall be made without set-off, counterclaim, withholding, deduction or other defense.
Without limiting the foregoing, all such payments shall be made free and clear of and without deduction or withholding for any
present or future taxes, levies, imposts, deductions, charges or withholdings, and all liabilities with respect thereto, excluding
taxes imposed on the net income of the Collateral Agent or any Buyer by the jurisdiction in which the Collateral Agent or
such Buyer is organized or where it has its principal lending office (all such nonexcluded taxes, levies, imposts, deductions,
charges, withholdings and liabilities, collectively or individually, “Taxes”). If any Guarantor shall be required
to deduct or to withhold any Taxes from or in respect of any amount payable hereunder or under any other Transaction Document:


 


(i)
the amount so payable shall be increased to the extent necessary so that after making all required deductions and withholdings
(including Taxes on amounts payable to the Collateral Agent or any Buyer pursuant to this sentence) the Collateral Agent or each
Buyer receives an amount equal to the sum it would have received had no such deduction or withholding been made,


 




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(ii)
such Guarantor shall make such deduction or withholding,


 


(iii)
such Guarantor shall pay the full amount deducted or withheld to the relevant Governmental Authority in accordance with applicable
law, and


 


(iv)
as promptly as possible thereafter, such Guarantor shall send the Collateral Agent or each Buyer an official receipt (or, if an
official receipt is not available, such other documentation as shall be satisfactory to the Collateral Agent, as the case may
be) showing payment. In addition, each Guarantor agrees to pay any present or future stamp or documentary taxes or any other excise
or property taxes, charges or similar levies that arise from any payment made hereunder or from the execution, delivery, registration
or enforcement of, or otherwise with respect to, this Guaranty or any other Transaction Document (collectively, “Other
Taxes”).


 


(b)
Each Guarantor hereby indemnifies and agrees to hold each Indemnified Party harmless from and against Taxes or Other Taxes
(including, without limitation, any Taxes or Other Taxes imposed by any jurisdiction on amounts payable under this Section
12) paid by any Indemnified Party as a result of any payment made hereunder or from the execution, delivery, registration
or enforcement of, or otherwise with respect to, this Guaranty or any other Transaction Document, and any liability
(including penalties, interest and expenses for nonpayment, late payment or otherwise) arising therefrom or with respect
thereto, whether or not such Taxes or Other Taxes were correctly or legally asserted. This indemnification shall be paid
within thirty (30) days from the date on which the Collateral Agent or such Buyer makes written demand therefor, which demand
shall identify the nature and amount of such Taxes or Other Taxes.


 


(c)
If any Guarantor fails to perform any of its obligations under this Section 12, such Guarantor shall indemnify the Collateral
Agent and each Buyer for any taxes, interest or penalties that may become payable as a result of any such failure. The obligations
of the Guarantors under this Section 12 shall survive the termination of this Guaranty and the payment of the Obligations
and all other amounts payable hereunder.


 


Section
13. Indemnification.


 


(a)
Without limitation of any other obligations of any Guarantor or remedies of the Collateral Agent or the Buyers under this Guaranty
or applicable law, except to the extent resulting from any Indemnified Party’s gross negligence or willful misconduct, as
determined by a final judgment of a court of competent jurisdiction no longer subject to appeal, each Guarantor shall, to the
fullest extent permitted by law, indemnify, defend and save and hold harmless the Collateral Agent and each Buyer and each of
their affiliates and their respective officers, directors, employees, agents and advisors (each, an “Indemnified Party”)
from and against, and shall pay on demand, any and all claims, damages, losses, liabilities and expenses (including, without limitation,
reasonable fees and expenses of counsel) that may be incurred by or asserted or awarded against any Indemnified Party in connection
with or as a result of any failure of any Guaranteed Obligations to be the legal, valid and binding obligations of any Transaction
Party enforceable against such Transaction Party in accordance with their terms.


 




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(b)
Each Guarantor hereby also agrees that none of the Indemnified Parties shall have any liability (whether direct or indirect, in
contract, tort or otherwise) or any fiduciary duty or obligation to any of the Guarantors or any of their respective affiliates
or any of their respective officers, directors, employees, agents and advisors, and each Guarantor hereby agrees not to assert
any claim against any Indemnified Party on any theory of liability, for special, indirect, consequential, incidental or punitive
damages arising out of or otherwise relating to the facilities, the actual or proposed use of the proceeds of the advances, the
Transaction Documents or any of the transactions contemplated by the Transaction Documents.


 


Section
14. Miscellaneous.


 


(a)
Each Guarantor will make each payment hereunder in lawful money of the United States of America and in immediately available funds
to the Collateral Agent or each Buyer, at such address specified by the Collateral Agent or such Buyer from time to time by notice
to the Guarantors.


 


(b)
No amendment or waiver of any provision of this Guaranty and no consent to any departure by any Guarantor therefrom shall in any
event be effective unless the same shall be in writing and signed by each Guarantor, the Collateral Agent and each Buyer, and
then such waiver or consent shall be effective only in the specific instance and for the specific purpose for which given.


 


(c)
No failure on the part of the Collateral Agent or any Buyer to exercise, and no delay in exercising, any right or remedy hereunder
or under any other Transaction Document shall operate as a waiver thereof, nor shall any single or partial exercise of any right
hereunder or under any Transaction Document preclude any other or further exercise thereof or the exercise of any other right
or remedy. The rights and remedies of the Collateral Agent and the Buyers provided herein and in the other Transaction Documents
are cumulative and are in addition to, and not exclusive of, any rights or remedies provided by law. The rights and remedies of
the Collateral Agent and the Buyers under any Transaction Document against any party thereto are not conditional or contingent
on any attempt by the Collateral Agent or any Buyer to exercise any of their respective rights or remedies under any other Transaction
Document against such party or against any other Person.


 


(d)
Any provision of this Guaranty that is prohibited or unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective
to the extent of such prohibition or unenforceability without invalidating the remaining portions hereof or affecting the validity
or enforceability of such provision in any other jurisdiction.


 


(e)
This Guaranty is a continuing guaranty and shall (i) remain in full force and effect until Payment in Full of the Guaranteed Obligations
(other than inchoate indemnity obligations) and shall not terminate for any reason prior to the respective Maturity Date of each
Note (other than Payment in Full of the Guaranteed Obligations) and (ii) be binding upon each Guarantor and its respective successors
and assigns. This Guaranty shall inure, together with all rights and remedies of the Collateral Agent hereunder, to the benefit
of and be enforceable by the Collateral Agent, the Buyers, and their respective successors, and permitted pledgees, transferees
and assigns. Without limiting the generality of the foregoing sentence, the Collateral Agent or any Buyer may pledge, assign or
otherwise transfer all or any portion of its rights and obligations under and subject to the applicable terms of the Securities
Purchase Agreements or any other Transaction Document to any other Person in accordance with the terms thereof, and such other
Person shall thereupon become vested with all the benefits in respect thereof granted to the Collateral Agent or such Buyer (as
applicable) herein or otherwise, in each case as provided in the Securities Purchase Agreements or such Transaction Document.
None of the rights or obligations of any Guarantor hereunder may be assigned or otherwise transferred without the prior written
consent of each Buyer.


 




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(f)
This Guaranty and the other Transaction Documents reflect the entire understanding of the transaction contemplated hereby and
shall not be contradicted or qualified by any other agreement, oral or written, entered into before the date hereof.


 


(g)
Section headings herein are included for convenience of reference only and shall not constitute a part of this Guaranty for any
other purpose.


 


Section
15. Currency Indemnity.


 


If,
for the purpose of obtaining or enforcing judgment against Guarantor in any court in any jurisdiction, it becomes necessary to
convert into any other currency (such other currency being hereinafter in this Section 15 referred to as the “Judgment
Currency”) an amount due under this Guaranty in any currency (the “Obligation Currency”) other than
the Judgment Currency, the conversion shall be made at the rate of exchange prevailing on the Business Day immediately preceding
(a) the date of actual payment of the amount due, in the case of any proceeding in the courts of courts of the jurisdiction that
will give effect to such conversion being made on such date, or (b) the date on which the judgment is given, in the case of any
proceeding in the courts of any other jurisdiction (the applicable date as of which such conversion is made pursuant to this Section
15 being hereinafter in this Section 15 referred to as the “Judgment Conversion Date”).


 


If,
in the case of any proceeding in the court of any jurisdiction referred to in the preceding paragraph, there is a change in the
rate of exchange prevailing between the Judgment Conversion Date and the date of actual receipt of the amount due in immediately
available funds, the Guarantors shall pay such additional amount (if any, but in any event not a lesser amount) as may be necessary
to ensure that the amount actually received in the Judgment Currency, when converted at the rate of exchange prevailing on the
date of payment, will produce the amount of the Obligation Currency which could have been purchased with the amount of
the Judgment Currency stipulated in the judgment or judicial order at the rate of exchange prevailing on the Judgment Conversion
Date. Any amount due from the Guarantors under this Section 15 shall be due as a separate debt and shall not be affected
by judgment being obtained for any other amounts due under or in respect of this Guaranty.


 


Section
16. Amendment and Restatement.


 


This
Guaranty constitutes an amendment, modification and restatement of the Existing Guaranty and shall not constitute a novation,
extinguishment or substitution of the obligations of the guarantors under the Existing Guaranty or in any way release or impair
the rights, duties, or obligations created pursuant to the Existing Guaranty or any other Transaction Documents (as defined in
the Existing Guaranty) or to release or otherwise adversely affect any lien, mortgage or security interest or any rights of the
Collateral Agent against any guarantor, surety or other party primarily or secondarily liable for any Obligation under the Existing
Security Agreement, and all of such rights, duties, obligations, and liens are assumed, ratified and affirmed by each Guarantor.


 


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IN
WITNESS WHEREOF, each Guarantor has caused this Guaranty to be executed by its respective duly authorized officer, as of the date
first above written.


 


	 	GUARANTORS:
	 	 
	 	LUCID
    DIAGNOSTICS, INC.
	 	 	                           
	 	By:	 
	 	Name:	
	 	Title:	


 


[Signatures
continue on following page]


 




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	ACCEPTED BY:	 
	 	 
	ALTO OPPORTUNITY MASTER 	 
	FUND, SPC - SEGREGATED MASTER
    	 
	PORTFOLIO B,	 
	as Collateral Agent	 
	 	 
	By:	                	 
	Name:		 
	Title: 		 


 




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